宁镇中段燕山期中酸性侵入岩的稀土和微量元素地球化学研究

REE AND TRACE ELEMENT GEOCHEMISTRY OF YANSHANIAN NEUTRAL-ACIDIC INTRUSIVE ROCKS IN THE MIDDLE NANJING-ZHENJIANG GRANITE PROVINCE

与铜多金属成矿相关的宁镇中段地区岩浆活动主要发生在燕山晚期,形成多个中酸性侵入岩体。文章在开展野外调查的基础上,主要从稀土元素和微量元素的实测资料,结合常量元素进行分析,探讨岩浆来源、结晶分异过程及铜多金属矿化特点。研究结果表明,宁镇中段岩浆为壳幔混合型,具有相同的演化趋势。并确定了6大岩体结晶分异程度的高低,提出了岩浆分异程度与矿化特点的关系。

Cu-polymetallic ore-forming magmatic activity in the middle Nanjing-Zhenjiang granite province occurred mainly in the late Yanshanian period. Based on the field investigation and geochemical characteristics of major elements, REE and other trace elements, this article has mainly discussed the magma origin and crystallization process and their relation to Cu-polymetallic mineralization. The results show that the magma in the whole area is of crust-mantle mixing origin, which has the same trend of the evolution. The crystallization differentiation degree of different intrusive bodies has also been identified, and the relationship between the degree of crystallization differentiation and mineralization characteristics has been put forward.